Factual error: It is claimed that a meteor shower has been diverted towards the Wheel by a star in M13 (the Hercules Cluster) going nova. As M13 is a globular cluster in the galactic halo, some 34,000 light years away from Earth, it would have to be one almighty nova to affect the course of a meteor shower in our solar system - due to the countless gravitational forces between M13 and the plane of the Milky Way - and been caused at least 34,000 years before the time of the story.
Plot hole: When the airlock door is opening at the end of the final episode, the Cyberman is the only one who appears to be affected by the air rushing out. Although 'rushing out' is probably overstating the speed of the 'explosive decompression'. It's not so much an explosion as a gentle breeze...
Character mistake: The Doctor (Patrick Troughton) makes one of the funniest fluffed lines in the entire history of Doctor Who in the final episode. With all sincerity he says "We'll all be dead soon, unless you switch over to the sexual air supply." (The word Troughton was probably looking for was "sectional.").
Plot hole: We twice see a map of how far the ice is away from the house, once in the first episode, and later in episode five. The ice has moved most of the way across the map in this time, and the distance it has moved is stated to be a 100 metres. This would place it only 20 metres from the base. The problem with the distance is that it takes Penley quite a while to get the injured Jamie to the base, including a stretch across open ground. Also, the Ice Warriors weapon targeter suggests the base is as much as two kilometres away. So just how far away is the ice; 20 metres, 2 kilometers...or somewhere in between?
Factual error: When the group divide up into parties, the leader says they need to be at the rocket at 1630, so meet here at 1625. He then goes on to say that will give them an hour to look for anyone that's missing. The other actors seem to notice his mistake because they either look puzzled or look off camera, probably seeing if anyone would shout "Cut."Matty W
Revealing mistake: During the fight scene between Toberman and the Cybercontroller, the Cybercontroller uses a very visible harness to lift Toberman over his head, and the wires attached to the harness Toberman is wearing are also very visible. When Toberman, in return, lifts the Cybercontroller above HIS head, it is obvious that what Toberman is lifting is an empty costume, with no-one inside it.
Audio problem: In episode 3 of this story it is noticeable that practically every sound in this episode has been re-dubbed and as a result is out of synch - sometimes quite badly. An example is when Milton Johns has his thugs break into Giles Kent's trailer - there's a three-second lag between the breaking of the plates and the sounds they make. (This may be simply due to the only surviving copies in the BBC Archives being these "badly dubbed" ones, recovered from obscure sources).